Schräge Musik installation in Ju 88G

Schräge Musik, German for Jazz Music (literally, "slanting" music), was the name given to installations of upward-firing cannons mounted in night fighters by the Luftwaffe during World War II. This allowed them to approach and attack British bombers from below, where they were basically invisible and there was no defensive guns to fire back at them.

Prior to the introduction of Schräge Musik, night fighters were simply heavy fighters equipped with radar in the nose. This meant that the fighter had to approach the target bomber from the rear in order to shoot at them, and RAF bombers were all equipped with fairly powerful rear turrets to help fend off such attacks. The main use of the turret was in fact surveillance, when a night fighter was seen approaching the gunner would call for the bomber to execute a sharp maneuver, which was typically successful in making the bomber disappear from the fighter's radar.

Night fighter pilots then developed a new tactic to avoid the turrets. Instead of approaching from directly to the rear, they would approach about 1500ft below the plane. They would then pull up sharply and start firing when the nose of the bomber appeared in the gunsight. As their plane slowed and the bomber passed over them, the entire lower fuselage was sprayed with fire. However effective, this maneuver was quite difficult to arrange, and also led to the possibility of a collision.

Oberleutnant Rudolf Schönert decided to experiment with upward firing guns in 1941. The first installation was made late in 1942, in a Dornier Do 17Z-10 that was also equipped with Lichtenstein radar. Apparently the tests were not terribly successful, and the matter was dropped. Schönert nevertheless fitted his next aircraft, a Messerschmitt Bf 110, with two 20mm MG 151/20 cannons attached to the rear wall of the cockpit, and shot down a bomber with them in May 1943. That summer he took command of the II/NJG 5 night fighter unit, and received three Do 217J's for testing with his system.

Schräge Musik was first used operationally on the RAF raids on Peenemünde on the night of August 17, 1943. Three waves of aircraft bombed the area, and successful radar countermeasures by the RAF meant that only the last of the three waves was met by any sizable group of night fighters. The two Groups of the third wave, the 5th and Canadian 6th, lost 29 of their 166 planes, well over the 10% losses considered "unsustainable". In this raid lost 40 aircraft in total; 23 Lancasters, 15 Halifaxes, and 2 Stirlings.

Wide-scale adoption followed in late 1943, and in 1944 a third of all German nightfighters carried upward-firing guns. An increasing number of these installations used the more powerful MK 108 cannon, such as those fitted to the Heinkel He 217 and Junkers Ju 88G. The definitive night fighter version of the Messerschmitt Me 262 was also to have carried such an installation, but none were built before the end of the war.

Similar systems were tested on day fighters as well, known as Sondergeräte and Jägerfaust. In these cases, the aim was to provide the fighters with a very powerful single-shot weapon, as opposed to one that allowed them to operate unseen.

An attack by a Schräge Musik equipped fighter was typically a completely surprise to the bomber, only realizing a fighter was close by when one of the wings or engines would burst into flame. Had it not been for the ever-increasing abilities of the British anti-radar efforts, the introduction of newer aircraft designs and Schräge Musik would have seriously depleated RAF Bomber Commands forces.